Intelligent Solar Panel Array

ABSTRACT

An intelligent solar panel array is disclosed. The array comprises a master panel and a plurality of client panels connected by a predetermined scheme. All panels further comprise a plurality of solar energy collection modules, a supporting, pivoting and tilting mechanism, a controller and a short range communication unit. The communication units of panels form an ad hoc communication network. The master panel further comprises another communication unit for communicating with a server through an existing communication network such as the Internet. At a moment of operation, the optimized position of the master panel towards the sun is determined by measuring current-voltage curve at multiple positions. The optimized position is transmitted to all client panels through the ad hoc communication network. All panels therefore generate electrical power based upon the optimized positions towards the sun.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND

1. Field of Invention

This invention relates to solar energy collection, specifically to asystem and method of maximizing solar energy collection from a solarpanel array.

2. Description of Prior Art

In recent years, concerns have been raised that high demand forelectricity taxing the capacity of existing electricity generatingplants. Furthermore, concerns regarding the availability andenvironmental safety of fossil and nuclear fuel are being raised. As aresult of the above factors, the price of electricity has been on a pathof steady increasing. It has become increasing common to seek foralternative energy sources. One such energy source is the sun. Solarpanels have been available for many years for the purpose of convertingthe energy from sunlight into electricity. The collected energy isthereafter often stored in some sort of energy bank and used for heatinghomes, water suppliers, and powering various electrical devices. Thecollected energy in a form of DC (Direct Current) electricity may alsobe injected into a power grid after it is converted into AC (AlternativeCurrent) electricity by an inverter.

In order for the solar panel to receive as much solar energy as possiblefor conversion into electricity, it is desirable to mount the solarpanel on an adjustable support apparatus that allows for variablyorienting the solar panel relative to the general position of the sun.Many existing devices generally provide for tilting and rotation of thepanel. Tilting of the panel is generally provided by a pivotalconnection at the bottom of the panel and a drive mechanism of somesort, with the panel bottom either directly hinged to a base of somesort or hingedly connected to a rigid non-extendable linkage. Several ofthese devices also provide for rotation of the panel. The rotation isusually provided by separately rotating the support apparatus such as apole or a plate for the entire panel.

As the sun moves across the sky from sunrise to sunset, it is desirablethat the orientation of the solar panel is changed accordingly by thepivoting and tilting mechanism of the support apparatus to maintain anoptimized position for generating highest electricity from the sunlight.

A clock mechanism has been employed to control the orientation of thepanel. To compensate for the compound movement of the sun, daily fromhorizon to horizon, and seasonally with a progressing season elevation,the clock mechanism must be elaborate and therefore expensive.

Sensors such as illumination detectors have also been employed to derivethe position of the sun. U.S. Pat. No. 4,297,572 to Carlton disclosed asolar energy collector assembly including a solar panel mounted formovement along a predetermined tracking path in order to maintain apredetermined orientation with respect to the sun. The disclosedassembly also includes a specific solar tracking sensor. There are manyproblems associated with the use of illumination detectors in thetracking mechanism including shadowing of the detector by a cloud in thesky.

A solar panel array comprising a multiple solar panels connectedtogether in series and/or in parallel has recently become more and morepopular, in particularly, for use as a power generation plant. It isimportant that the array generates highest possible electrical power tospeed up the return on investment (ROI). Low cost wireless communicationnetwork has been proposed to enhance the operation efficiency of thearray.

In US patent publication 2008/0087321 by Schwartzman, a solar energygenerator module is disclosed including a modular photovoltaic array,sensors, controller and communication means for monitoring andcommunicating a variety of physical parameters from each module to acentralized computer. The collected information can be utilized tomonitor module health for maintenance purposes, and also be used as aposition input for the primary servomechanism control algorithm.

In US patent publication 2009/0188488 by Kraft et al., an apparatus fornetworking solar tracking devices is disclosed. The system includes oneor more solar tracking devices, each comprising a tracking controller.Tracking controllers form a wireless mesh communication network managedby a network manager. Tracking controller receives operation data fromand sends monitor data to host computer.

The potential to increase the efficiency of the solar array by employinga low cost communication network connectable to the Internet, however,has not yet been fully explored. It is desirable to have an intelligentsolar panel array which can maximize the generated electricity withacceptable cost.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a novelsolar panel array for generating highest electrical power from thesunlight without employing a dedicated illumination detector.

It is another object of the present invention to provide a novel systemand method for maximizing generated electricity of a solar panel arrayby employing an ad hoc communication network comprising communicationdevices embedded in each solar panel.

A solar panel comprises a plurality of solar modules installed on anapparatus with a supporting, pivoting and tilting mechanism, acontroller, and a communication device. The optimized orientation(position) for the panel is determined by pivoting and/or the panel tomultiple positions in a sequential manner. At each position, thegenerated DC current and voltage is measured by a measurement unit. Themaximum power point is then determined based upon the measuredcurrent-voltage curve. The optimized position for generating the highestelectrical power is decided by comparing all recorded maximum power ateach position. Since it is a direct measurement on the generated currentand voltage from the solar panel, no dedicated illumination detector isrequired.

A solar panel array is formed by a number of solar panels connected in apredetermined scheme. One of the panels is a master panel and the restof the panels are client panels. Communication devices from the panelsform an ad hoc communication network. The master panel may have anothercommunication means for connecting directly to a server (host computer)through an existing communication network such as the Internet. Theoptimized position determined by the master panel may be sent to clientpanels through the communication network. All panels are adjusted to theoptimized position for generating the highest electrical power. Thedescribed method may be repeated in a predetermined frequency during thedaytime.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and itsvarious embodiments, and the advantages thereof, reference is now madeto the following description taken in conjunction with the accompanyingdrawings.

FIG. 1 is a schematic diagram of a solar panel array with a master paneland multiple client panels.

FIG. 2 is a functional block diagram of an exemplary master panel and anexemplary client panel.

FIG. 3 is a schematic diagram of an exemplary communication module ofthe solar panel array with the mater panel communicating to each clientpanel in a parallel manner.

FIG. 4 is a schematic diagram of another exemplary communication moduleof the solar panel array with a means of master panel communicating to aclient panel through yet another client panel.

FIG. 5 is a flow diagram depicting steps of operations of determining anoptimized position for a panel by measuring current-voltage curve atmultiple positions.

FIG. 6 is a flow diagram depicting steps of operations that optimizedpositions for all panels in the array are determined.

FIG. 7 is a flow diagram depicting steps of operations thatfunctionality of panels are tested and are communicated to the server inthe communication network.

DETAILED DESCRIPTION

The present invention will now be described in detail with references toa few preferred embodiments thereof as illustrated in the accompanyingdrawings. In the following description, numerous specific details areset forth in order to provide a thorough understanding of the presentinvention. It will be apparent, however, to one skilled in the art, thatthe present invention may be practiced without some or all of thesespecific details. In other instances, well known process steps have notbeen described in detail in order not to unnecessarily obscure thepresent invention.

FIG. 1 is a schematic diagram of a solar panel array 100. The array 100comprises a mater panel 102 and a plurality of client panels 104.Although the panels are connected in a parallel manner as illustrated inan exemplary case, the panels can be connected in any configuration in acombination of in series and/or in parallel to generate a desired DCcurrent and voltage. The generated DC electricity may be converted intoAC electricity by an inverter and is subsequently injected into a powergrid. The generated DC electricity may also be used directly to powerelectrical devices or appliances. The generated DC power may also bestored in a storage device such as a battery.

FIG. 2 is a functional block diagram of the master panel 102 and aclient panel 104. The master panel 102 comprises a plurality of solarmodules 202 connected in a predetermined manner in series and/or inparallel. Each module may further comprise a plurality of solar cellsconnected in series and/or in parallel. Solar modules 202 are installedon an apparatus 204 that provides a structural support for 202 and alsoprovides a mechanism for pivoting and/or tilting the panel with a drivemechanism. A measurement unit 206 provides a means for measuring theoutput current and voltage of the panel. 206 may also provide a meansfor measuring the output current and voltage of one or several modulesof the panel 102. The operation of the master panel 102 is controlled bya controller 208. The panel 102 further comprises a first communicationunit 210 for communicating with client panels in the array. According toone embodiment, 210 is a short range communication device that mayconform to a variety of short range communication standard such asBluetooth (IEEE 802.11b and its amendments), Zigbee (IEEE 802.15.4 andits amendments) and WiFi (IEEE 802.11 and its amendments). The panel 102further comprises a second communication unit 212 for communicating witha server (host computer) through an existing communication network suchas the Internet. 210/212 may be separate units. 210/212 may also be anintegrated unit. 210/212 may be an integrated part of 208. The operationof the panel may be powered by a power supply 214. In one aspect of thepresent invention, 214 may be a battery. The battery may be rechargeableby the solar panel. In another aspect, the power supply 214 may be thesolar modules 202 or at least a portion of 202.

The client panel 104 comprises solar modules 216, an apparatus 218 forsupporting, pivoting and/or tilting the panel, a current and voltagemeasurement unit 220, a controller 222, and a power supply 226. Theclient panel 104 comprises a communication unit 224 conforming to thesame communication standard (s) as the first communication unit 210 ofthe master panel 102. The client panel 104 may not have a communicationunit for communicating with the server directly. It is, however,possible for the client panel 104 to communicate to the server throughthe first and the second communication units 210/212 of the master panel102. In an exemplary illustration of the communication path, a data fileincluding the operational status of the client panel 104 is sent to 210from 224. The received file is then sent to the second communicationunit 212 through a cache or a memory in the controller 208 and issubsequently sent to the server by the 212. In a similar manner, aninstruction from the server can be delivered to the client panel through212 to 210 and subsequently to 224 and be received by 222 for theexecution.

FIG. 3 is a schematic diagram of an exemplary communication module ofthe solar panel array 100 with the mater panel 102 communicating to eachclient panel 104 in a parallel manner. According to one embodiment ofthe communication module, the first communication unit 210 of the masterpanel 102 communicates to each communication unit 224 of client panel104 directly. The information such as the optimized position forgenerating highest electrical power at a particular time of the day canbe transmitted to each client panel through 210 and 224. On the otherhand, the operation status of each client panel 104 can be collected andtransmitted to the master panel 102 through 224/210. The communicationpaths are bi-directional. The master panel 102 may be connected by theuse of the second communication unit 212 to a server 302 through anexisting communication network 304. The network 304 may be the Internet.The network 304 may also be a private communication network.

There are numerous derivative implementations of present inventiveconcept. All such derivatives are fall into the spirit of the presentinventive concept. In an exemplary case, a server 302 may be connectedto the first communication unit 210 of the master panel 102 directly andto other communication unit 224 through 210 and be a part of the ad hoccommunication network. The server 302 can then be connected to any ofother servers in the Internet or to any of other communication networks.In another exemplary case, the server may be connected to communicationunits 210 and 224 directly and be part of the ad hoc communicationnetwork.

FIG. 4 is a schematic diagram of another exemplary case of thecommunication module of the solar panel array 100. Some of the clientpanel communication units 224 may communicate to the communication unit210 directly. Some of other communication units 224 may communicate to210 through one or several communication unit 224 as is typical for anad hoc communication network.

FIG. 5 is a flow diagram depicting steps of operations of determining anoptimized position for a panel by measuring current-voltage curve atmultiple positions. The positions may be predetermined and are stored inthe controller 208 of the master panel 102. The positions may also bedetermined in a real time base by the controller 208. Process 500 startswith step 502 that the panel 102 is moved to a predetermined position bypivoting and/or tilting the panel through a drive mechanism. Current andvoltage relationship is then measured by the measurement unit 206 withina preset operation range and may be recorded in a memory of thecontroller 208 according to step 504. The maximum power point for theposition is determined and recorded in step 506. Steps 502 to 506 arerepeated until all predetermined positions are tested. If it is verifiedin step 508 that all predetermined positions have been tested, theoptimized position for generating the highest electrical power issubsequently determined based on a predetermined algorithm in step 510.According to one aspect of the present invention, the optimized positionmay be determined by comparing each maximum power for each position andby selecting the position corresponding to the highest maximum power.According to another aspect of the present invention, the optimizedposition may also be determined by a more elaborate algorithm byplotting the maximum power at each position against their coordinates.The optimized position for determining the highest electrical power canthen be extrapolated based upon an algorithm for finding the peak valueof the plot. The method is well know in the art and can be implementedby a computing program and be executed by the controller 208. In anotherimplementation, the collected data may be sent to the server 302 through304. The optimized position may be determined by the server 302 and besent back to the master panel 102. After determination of the optimizedposition, the panel 102 is adjusted to the position to generate thehighest electrical power in step 512.

FIG. 6 is a flow diagram depicting steps of operations that optimizedpositions for all panels in the array are determined by the use of thead hoc communication network formed by the communication units 210/224.Process 600 starts with step 602 that each client panel 104 iscalibrated to the master panel 102. The calibration process will ensurethat when the optimized position for the master panel 102 is determined,the position for each client panel 104 can be derived accurately fromthe received data file including the optimized position for the masterpanel 102 even though there may be a mismatch due to the impaction fromsuch as for example, the installation work. The optimized position forthe master panel 102 at a particular time of the day is determined instep 604 by employing the operation as depicted in the process 500. Theoptimized position for each client panel 104 is subsequently determinedin step 606 based upon the received optimized position for the masterpanel 102. The data file may also include the calibration data if it isstored in the memory of the controller 208. The calibration data mayalso be stored locally in the controller 222 of the client panel 104.All panels are then adjusted to the optimized positions in step 608 bypivoting and/or tilting the panel using the drive mechanism.

FIG. 7 is a flow diagram depicting steps of operations thatfunctionality of panels is tested and communicated to the server 302connected to the communication network 304. Process 700 starts with step702 that an instruction for testing functionality is sent out from thecommunication unit 210 of the master panel 102 through the ad hoccommunication network. In step 704, the instruction is received by thecommunication unit 224 of each client unit 104. The controller 222 in104 controls an operation of testing functionality in step 706. Thetesting may be a simple operation of measuring of the output current andvoltage of the panel. The testing may involve more completed tasks asinstructed by the server 302 through the master panel 102. If thefunctionality is verified as normal in step 708, the operation ofconverting solar energy into the electricity will be started or becontinued in step 710. If the functionality test fails in step 710, thefault panel may be switched off in step 712 and an error message is sentto the controller 208 through 224/210. The error messages may be furthersent to the server 302 through the communication unit 212 and thenetwork 304. A data file indicating the normality of the client panelsmay also be sent to the master panel 102 and to the server 302 in asimilar manner. The operational status of the mater panel 102 may alsobe collected and be sent to the server 302 through the network 304.

While the invention has been disclosed with respect to a limited numberof embodiments, numerous modifications and variations will beappreciated by those skilled in the art. It is intended that all suchvariations and modifications fall within the scope of the followingclaims:

1. A solar energy collection system comprising: (a) one master panelcomprising a plurality of solar energy collection modules, a supporting,pivoting and tilting mechanism, a controller, a first communicationunit, a second communication unit, and a means of determining theoptimized position towards the sun for generating highest electricalpower; (b) at least one client panel comprising a plurality of solarenergy collection modules, a supporting, pivoting and tilting mechanism,a controller, a communication unit, and a means of determining theoptimized position towards the sun for generating highest electricalpower based on a received data file including the optimized position forsaid master panel through a communication means provided by thecommunication units.
 2. The system as recited in claim 1, wherein saidmeans of determining the optimized position of the master panelcomprising: (a) a means of pivoting and/or tilting the master panel to aplurality of predetermined positions; (b) a means of measuring themaximum generated power at each position by a measurement unit; and (c)a means of deriving the optimized position from all measured data basedupon a predetermined algorithm.
 3. The system as recited in claim 2,wherein said predetermined algorithm including: (a) determining theoptimized position by comparing maximum power at each position andselecting the position corresponding to the highest power generation;and (b) determining the optimized position by an algorithm ofextrapolating the optimized position from all measured data.
 4. Thesystem as recited in claim 1, wherein said means of determining theoptimized position of the client panel further including a means ofderiving the position from the optimized position of the master paneland from a calibration file reflecting at least installation mismatchamong the client panel and the master panel.
 5. The system as recited inclaim 1, wherein the first communication unit of the master panelfurther comprising a transceiver conforming to a standard or acombination of standards from the following group: (a) ZigBee (IEEE802.15.4 and its amendments); (b) Bluetooth (IEEE 802.11b and itsamendments); and (c) WiFi (IEEE 802.11 and its amendments).
 6. Thesystem as recited in claim 1, wherein said communication unit of saidclient panel further comprising a transceiver conforming to the samecommunication standard as the first communication unit of said masterpanel.
 7. The system as recited in claim 1, wherein said secondcommunication unit of said master panel further comprising a transceiverfor communicating with an existing communication network including theInternet.
 8. The system as recited in claim 1, wherein said mater paneland said client panel further comprising a power supply including abattery.
 9. The system as recited in claim 8, wherein said power supplyfurther comprising at least a portion of said solar energy collectionmodules.
 10. A method of generating highest electrical power from asolar panel comprising a plurality of solar modules and a supporting,pivoting and tilting mechanism controlled by a controller, the methodcomprising: (a) pivoting and/or tilting said solar panel to a pluralityof predetermined positions in a sequential manner; (b) measuringgenerated current and voltage by a measurement unit in a preset rangeand determining the maximum electrical power at each of thepredetermined positions; (c) determining the optimized position fromwhich the highest electrical power is generated based on a predeterminedalgorithm; and (d) pivoting and/or tilting said solar panel to theoptimized position for generating the electrical power.
 11. The methodas recited in claim 10, wherein said step (a) is controlled by acomputing program pre-stored in a memory of the controller.
 12. Themethod as recited in claim 10, wherein said predetermined algorithm instep (c) further including: (a) determining the optimized position bycomparing maximum power at each position and selecting the positioncorresponding to the highest power generation; and (b) determining theoptimized position by an algorithm of extrapolating the optimizedposition from all measured data.
 13. The method as recited in claim 10,wherein said method further comprising steps of repeating the steps froma) to d) at a predetermined time interval.
 14. A method of generatinghighest electrical power from a plurality of solar panels comprising aplurality of solar modules, a supporting, pivoting and tilting mechanismcontrolled by a controller, and at least one communication unit, themethod comprising: (a) determining optimized position for generatinghighest power towards the sun of one panel; (b) transmitting a data fileincluding determined position to all other panels by the communicationunits; (c) pivoting and/or tilting all panels to the optimized positionsbased upon received data file; and (d) generating electrical power byall the panels.
 15. The method as recited in claim 14, wherein saidmethod further comprising a step of calibrating original positions ofeach panel, whereby the method ensures that the optimized position foreach panel is achieved even when there is a difference of originalposition due to imperfection in installation of the panels.
 16. Themethod as recited in claim 14, wherein said operation of “transmitting”in step (b) is based upon an ad hoc communication network formed by thecommunication units from each panel.
 17. The method as recited in claim16, wherein the ad hoc communication network conforming to a standard ora combination of standards from the following group: (a) ZigBee (IEEE802.15.4 and its amendments); (b) Bluetooth (IEEE 802.11b and itsamendments); and (c) WiFi (IEEE 802.11 and its amendments).
 18. Themethod as recited in claim 14, wherein at least one of the panelscomprising another communication unit for communicating with an existingcommunication network.
 19. The method as recited in claim 18, whereinsaid existing communication network is the Internet.
 20. The method asrecited in claim 14, wherein said method further comprising a step oftesting functionality of each panel after receiving an instruction byits communication unit and sending the test results to a server throughan communication network formed by communication units.